I just launched the project, so can't say it helped me professionally yet.
Almost all of the time invested in this was pre-AI. I agree it's harder to justify those deep dives but still worth it if you do it alongside AI IMO.
Even if the project didn't become popular. Have you been able to use it as part of your portfolio to get a job, or move into academia ? Perhaps what you learned in the project was useful in some other way ?
I have used it when applying to some jobs but no success so far.
I think this project was useful because it allowed me to go deeper than I ever had in code. I had very though issues that required me to ask in forums etc. I had a bug with ray-triangle intersection that took me 3 months to find the cause. So it was good training and it's a great project to have on my portfolio. I'm sure it can help me if I apply for something related to computer graphics and maybe gaming.